Space port blast kills three

SpaceShipOne, seen here, performed the first privately funded human spaceflight in 2004. On Thursday, a blast during testing of a follow-on vehicle killed three employees of Scaled Composites, the aerospace development company.

Jim Campbell (Aero-News Network)

SpaceShipOne glides back to Earth after its second flight into suborbital space.

Jim Campbell, Aero-News Network

July 27, 2007 T hree people have died from an explosion at the Mojave Air and Space Port in Mojave, California, about 80 miles north of Los Angeles. Two of the three died as a result of Thursday's blast, and a third person died today, a nursing supervisor at Kern Medical Center in Bakersfield told CNN.

All six people were employees of Scaled Composites. Aerospace engineer Burt Rutan founded the aerospace development firm, which developed SpaceShipOne — an air-launched suborbital spaceplane that completed the first privately funded human spaceflight June 21, 2004.

The blast occurred during a test of nitrous-oxide-fueled rocket motor components for SpaceShipTwo — a craft designed to carry passengers into suborbital flights. The vehicle is being developed as a joint venture between Scaled Composites and Virgin Group Limited. At the time of the explosion, nitrous oxide was flowing through the motor's fuel injectors during a "cold fire test."

"We were doing a test that we believed was completely safe," said Rutan. "We don't know why it exploded."